There is a typo in the first chart (table 4). It is $2684 per kg, not $2864 per kg for the Falcon 9. According to @LouScheffer.

Quote from: LouScheffer

It's even better than it looks - there's a typo in the table. The SpaceX entry should be 2684 $/kg, not 2864.

This is immediately clear when you ask how Proton can be comparable. They payload is 23,000 vs 22,800, or about 1% more. But the cost is more than 1% higher. So at least one of the numbers must be wrong, and it's SpaceX.

There is a typo in the first chart (table 4). It is $2684 per kg, not $2864 per kg for the Falcon 9. According to @LouScheffer.

Quote from: LouScheffer

It's even better than it looks - there's a typo in the table. The SpaceX entry should be 2684 $/kg, not 2864.

This is immediately clear when you ask how Proton can be comparable. They payload is 23,000 vs 22,800, or about 1% more. But the cost is more than 1% higher. So at least one of the numbers must be wrong, and it's SpaceX.

No need for reputation here. The table itself has all the data. The cost is 61.2 million. The payload is 22,800 kg. That gives a cost of $2684/kg. But the cost per kg entry, on the same line, says $2864. Seems pretty clear this is just a typo, since your calculator can show you that $2684 is the correct value.

No need for reputation here. The table itself has all the data. The cost is 61.2 million. The payload is 22,800 kg. That gives a cost of $2684/kg. But the cost per kg entry, on the same line, says $2864. Seems pretty clear this is just a typo, since your calculator can show you that $2684 is the correct value.

Just a question: why is price per kg the most quoted criteria regarding prices of launch?

When contracting a launch, you don't say "we only take up 50% of your mass capabilities, we will only pay 50% of the launch". You pay for a launch, unless you do some ride share mission. Launches have fixed costs, and potentially NRE costs for different payload interface structures (if multiple payloads were on flight)

Also generally payloads do not get up to the 80% to 100% capacity range of the launch vehicles; you would actually be paying a much higher $/kg on those missions.

edit: I feel like it's akin to buying a sedan vs an SUV/Minivan. The SUV/Minivan may cost $38k vas $26k of a sedan, but the SUV holds 7 people. You are saying "I'm paying $5.4k per person with a SUV vs $6.5k for a sedan" even though you only carry 4 people.

Just a question: why is price per kg the most quoted criteria regarding prices of launch?

When contracting a launch, you don't say "we only take up 50% of your mass capabilities, we will only pay 50% of the launch". You pay for a launch, unless you do some ride share mission. Launches have fixed costs, and potentially NRE costs for different payload interface structures (if multiple payloads were on flight)

Also generally payloads do not get up to the 80% to 100% capacity range of the launch vehicles; you would actually be paying a much higher $/kg on those missions.

edit: I feel like it's akin to buying a sedan vs an SUV/Minivan. The SUV/Minivan may cost $38k vas $26k of a sedan, but the SUV holds 7 people. You are saying "I'm paying $5.4k per person with a SUV vs $6.5k for a sedan" even though you only carry 4 people.

Obviously, $/kg is a simplified figure: it's one number, it could hardly ever be anything other than simplified. The benefit is the ability to compare product offerings or design approaches across a wide variety of sizes without having to stick a caveat of payload or capability on each one. The selection of a specific launcher for a specific mission doesn't just boil down to a comparison of $/kg between the launchers that are considered, but it can inform discussion to look at it when we want to compare broader categories of vehicles.

If a specific category of rockets (e.g. smallsat launchers like Pegasus or Electron have a significantly higher $/kg than larger vehicles (say, those with payloads >4 tons), which explains why multiple launching on larger vehicles is preferable for cubesats or smaller satellites like Orbcomm when conditions can allow sharing. If a specific manufacturer or vehicle production approach yields lower or higher $/kg across the board, then it offers a start to asking "what are they doing right/wrong?" and a basis for suggesting what LVs might exist in the future.

In your car example, I could say that $38k SUV is pricier per capacity. If I look at other vehicles in the automaker's line and they also have a higher $/passenger than the sedan manufacturer across their other vehicles, then I can say that if they ever made a sedan, it might also be pricer.

Zapata has been involved in identifying the drivers for launch costs since at least the mid 90's and (I think) the mid 80's.

It's interesting that the Pegasus still seems the only option that's actually available for primary launches in the in 100s of Kg despite the highest $/Kg. It's a very expensive launcher for not much payload. Another interesting point is that for Atlas 401 and how reasonably priced they are.

Just a question: why is price per kg the most quoted criteria regarding prices of launch?

It's a fair question and the answer is it does give a single metric across the whole range of LV's.

But you're right, you don't buy lift by the lb or Kg, you buy by the launch.

The other issue is a small LV simply can't carry the load, in the same way a car can't tow a 40ft container. If you want that you need an 18 wheeler.

A more subtle point is those prices only apply to full loads. Musk has talked of sub 1000$/lb for FH launches provided there are more than 4 a year and they are fully loaded IE to 50+tonnes, suggesting multiple ride shares will be needed if people actually want to get that low a price per Kg to orbit.

Just a question: why is price per kg the most quoted criteria regarding prices of launch?

It's a fair question and the answer is it does give a single metric across the whole range of LV's.

But you're right, you don't buy lift by the lb or Kg, you buy by the launch.

The other issue is a small LV simply can't carry the load, in the same way a car can't tow a 40ft container. If you want that you need an 18 wheeler.

A more subtle point is those prices only apply to full loads. Musk has talked of sub 1000$/lb for FH launches provided there are more than 4 a year and they are fully loaded IE to 50+tonnes, suggesting multiple ride shares will be needed if people actually want to get that low a price per Kg to orbit.

Not true. Your thinking is somewhat stuck in the historical launch market paradigm... somewhat self-perpetuating if no one builds a drastically cheaper launch technology.

Blue Origin's New Glenn launching 400 OneWeb sats in 5 launches is the type of commodity payload that can use bulk capacity (modulo packing factor/volume limitations). Fuel deliveries to LEO is another.

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"If we shared everything [we are working on] people would think we are insane!"-- SpaceX friend of mlindner